account admin buyer charged ensure happening indicated paypal percentage product refund rules sale sales seller tax thank-you

I just had a sale that was charged tax, even though I have no tax indicated in my seller admin for that product and no tax percentage in the sales tax section of seller admin. Now I have to refund the sales tax to the buyer. Please advise how to keep this from happening in the future. Thank you.

Please ensure that you don't have any tax rules set in your PayPal account.